Upstream control elements of the proopiomelanocortin gene and their use

Abstract

The nucleic acid sequence of the POMC enhancer is disclosed herein. Sequences from the human, rat, rabbit, hamster, mouse, and cow POMC enhancer are disclosed. Hybrid transgenes, comprising a POMC transcriptional control element operably linked to a nucleic acid sequence encoding a marker are also enclosed. In addition, transgenic mice carrying a hybrid transgene including a POMC control element operably linked to a marker are disclosed herein.

1. An isolated proopiomelanocortin enhancer element, comprising a nucleic acid sequence set forth as SEQ ID NO: 15, wherein the isolated proopiomelanocortin enhancer element elevates transcription of a heterologous coding sequence in a host cell. 
     
     
       2. The isolated proopiomelanocortin enhancer element of  claim 1 , consisting of a nucleic acid sequence set forth as SEQ ID NO: 15. 
     
     
       3. The isolated proopiomelanocortin enhancer element of  claim 1 , operably linked to a promoter and a heterologous nucleic acid sequence, wherein the enhancer element directs expression of the heterologous nucleic acid sequence in a proopiomelanocortin neuron. 
     
     
       4. The isolated proopiomelanocortin enhancer element of  claim 1 , comprising a nucleic acid sequence set forth as SEQ ID NO: 10, or SEQ ID NO: 13. 
     
     
       5. The isolated enhancer element of  claim 4 , operably linked to a nucleic acid sequence encoding a heterologous polypeptide. 
     
     
       6. The isolated enhancer clement of  claim 5 , wherein the nucleic acid sequence encoding a heterologous polypeptide encodes an enzyme, a marker, antibiotic resistance polypeptide or an antigen. 
     
     
       7. The isolated enhancer element of  claim 5 , wherein the nucleic acid sequence encoding a polypeptide encodes green fluorescent protein. 
     
     
       8. The isolated enhancer element of  claim 1 , operably linked to a heterologous promoter. 
     
     
       9. An expression vector comprising the isolated enhancer element of  claim 1  and a promoter. 
     
     
       10. The expression vector of  claim 9 , wherein the vector is a viral vector. 
     
     
       11. The expression vector of  claim 9 , wherein the vector is a plasmid vector. 
     
     
       12. An isolated host cell transformed with the vector of  claim 9 . 
     
     
       13. The isolated host cell of  claim 12 , wherein the host cell is a eukaryotic cell. 
     
     
       14. The isolated host cell of  claim 12 , wherein the host cell is a prokaryotic cell. 
     
     
       15. An expression cassette comprising the POMC enhancer of  claim 1 , and a nucleic acid sequence encoding proopiomelanocortin comprising at least one exon, wherein a polylinker comprising a unique site for a restriction enzyme is inserted into the exon. 
     
     
       16. The isolated proopiomelanocortin enhancer element of  claim 1 , wherein the heterologous coding sequence encodes a marker polypeptide. 
     
     
       17. The isolated enhancer element of  claim 1 , comprising a nucleic acid sequence set forth as SEQ ID NO: 10. 
     
     
       18. The isolated enhancer element of  claim 1 , comprising a nucleic acid sequence forth as SEQ ID NO: 13. 
     
     
       19. An expression vector comprising the isolated enhancer element of  claim 16  and a promoter. 
     
     
       20. The vector of  claim 19 , wherein the vector is a viral vector. 
     
     
       21. The vector of  claim 19 , wherein the vector is a plasmid vector. 
     
     
       22. An isolated host cell transformed with the vector of  claim 19 . 
     
     
       23. The isolated host cell of  claim 22 , wherein the host cell is a eukaryotic cell. 
     
     
       24. The expression vector of  claim 19 , wherein the isolated enhancer element comprises a sequence set forth as SEQ ID NO: 13. 
     
     
       25. An isolated host cell transformed with the vector of  claim 19 , wherein the isolated enhancer element comprises a sequence set forth as SEQ ID NO:13.